近日，北京大学物理学院的Long Xiong与新疆大学的Zhao-Xiang Fang以及深圳大学的Rui Sun等人合作并取得一项新进展。经过不懈努力，他们对三维自旋轨道耦合简并费米气体的基态及拓扑性质进行研究。相关研究成果已于2023年12月21日在国际知名学术期刊《中国物理快报》上发表。

本文从理论上研究了三维自旋轨道耦合简并费米气体，并首次给出了其基态的解析表达式。这一研究为理解三维非常规超导体的拓扑特性提供了一个全新的视角，并揭示了平凡相和拓扑相区域之间的拓扑相变。此外，与传统的超导体相比，这种系统表现出更为丰富的库珀对行为。特别是，在具有相同自旋方向的双库珀对中，出现了特殊的行为模式，进一步推动了拓扑相变的发生。这项研究和讨论可以推广到其他类型的非常规超导体和光晶格领域。

据悉，存在自旋-轨道耦合的三维简并费米气体引发了各种物理发现和现象，近年来引起了人们的极大关注。

附：英文原文

Title: Ground State and Its Topological Properties of Three-Dimensional Spin-Orbit Coupled Degenerate Fermi Gases

Author: Long Xiong, Ming Gong, Zhao-Xiang Fang, and Rui Sun

Issue&Volume: 2023-12-21

Abstract: Three-dimensional (3D) degenerate Fermi gases in the presence of spin-orbit coupling, inducing various kinds of physical findings and phenomena, have attracted tremendous attention in these years. We investigate the 3D spin-orbit coupled degenerate Fermi gases in theory and first present the analytic expression of their ground state. Our study provides an innovative perspective into understanding of the topological properties of 3D unconventional superconductors, and describes the topological phase transitions in trivial and topological phase areas. Further, such a system is provided with a richer set of Cooper pairings than traditional superconductors. The dual Cooper pairs with same spin directions emerge and exhibit peculiar behaviors, leading to topological phase transitions. Our study and discussion can be generalized to some other types of unconventional superconductors and areas of optical lattices.

DOI: 10.1088/0256-307X/40/12/127402

Source: https://cpl.iphy.ac.cn/10.1088/0256-307X/40/12/127402